Frost Dates: First and last frost dates for La Verkin, UT
What's a safe temperature for tender plants? When the nightly temperature falls, frost can form, even above 32°, because the air is colder high above the ground and the frost can form up there and then fall down onto your garden and do some damage, even if it's 36° on the ground. So many factors come into play, including wind, concrete, houses, trees and other structures, etc etc etc. Because of all this, you might want to consider 36° as "the danger zone".
In your average springtime, you have a 90% chance that there will be no 36° nights by May 24. In other words, you can pretty much count on being safe from frost by that day. But we want to get those tomatoes in the ground as soon as possible, right? We see that there's still an 80% chance of 36° on April 15, so we don't dare plant that early. We wait a few days and by May 1 we are at the 50/50 point. At this point, we are close and we can start watching the weather forecast. If the upcoming week's forecast doesn't show below 40°, then it's probably okay to risk planting out your plants.
Temperature | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
---|---|---|---|---|---|---|---|---|---|
Last 16° | Feb 13 | Feb 3 | Jan 26 | Jan 19 | Jan 12 | Jan 4 | Dec 25 | -- | -- |
Last 20° | Mar 1 | Feb 19 | Feb 12 | Feb 6 | Feb 1 | Jan 26 | Jan 20 | Jan 13 | Jan 3 |
Last 24° | Mar 18 | Mar 9 | Mar 2 | Feb 24 | Feb 19 | Feb 13 | Feb 7 | Jan 31 | Jan 22 |
Last 28° | Apr 16 | Apr 6 | Mar 30 | Mar 23 | Mar 18 | Mar 12 | Mar 5 | Feb 26 | Feb 16 |
Last 32° | Apr 30 | Apr 20 | Apr 14 | Apr 8 | Apr 3 | Mar 28 | Mar 22 | Mar 16 | Mar 6 |
Last 36° | May 24 | May 16 | May 10 | May 5 | May 1 | Apr 26 | Apr 21 | Apr 15 | Apr 7 |
The charts on this page show the probabilities of receiving a certain temperature on a certain day. Some examples that might help:
- You have a small 20% chance of getting 32° by October 20.
- There is a 50% chance of being hit by a 32° frost starting around October 30
- You have a 80% chance of seeing 32° by November 8
- Said another way, you have a 1 in 5 chance at making it to that day without a 32° night.
Temperature | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
---|---|---|---|---|---|---|---|---|---|
First 16° | Dec 2 | Dec 11 | Dec 18 | Dec 25 | Dec 31 | Jan 7 | Jan 18 | -- | -- |
First 20° | Nov 17 | Nov 23 | Nov 27 | Dec 1 | Dec 4 | Dec 8 | Dec 11 | Dec 16 | Dec 22 |
First 24° | Nov 5 | Nov 10 | Nov 14 | Nov 17 | Nov 20 | Nov 23 | Nov 26 | Nov 30 | Dec 5 |
First 28° | Oct 26 | Oct 31 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 23 |
First 32° | Oct 15 | Oct 20 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 8 | Nov 13 |
First 36° | Oct 6 | Oct 11 | Oct 15 | Oct 18 | Oct 21 | Oct 24 | Oct 27 | Oct 31 | Nov 5 |
Data is provided by the NOAA National Centers for Environmental Information.